That was tough haha! I'm not sure if I missed it on the page or in the game somewhere, but I didn't know that I had to use the spacebar! I also wasn't sure exactly where the lava started (the animations and wavy effects looked nice! but it meant that I wasn't sure what the limit was) and those spikes felt really big for how small sized the game is
That all being said, once you get going it's an addictive little challenge! Nice one!
EDIT: It totally says it on the page that spacebar is what you need to use. My bad!